Need help, Substrate in a Large FOWLR tank?

[95harley]

I am about to embark on converting a 240 (96x24x24) tank into an Agg FOWLR tank. It has a Wet/Dry on it with Bio Balls , but has been running fresh water for about 2.5 - 3 yrs now. I have several questions that I need help with.
I also have a 75 FOWLR tank with a crushed coral substrate that I vaccum syphon with a python vaccum every month. It has a Wet/Dry as well as a cannister and skimmer on it.
I realize the CC problem now and all the black clouds of dust that come up everytime I vaccum the tank and don't want a repeat problem on the 240. So here goes with some questions:
I read here that sand is better for not trapping all the debris in. With a group of large carnivour fish: Lions, Groupers, Tusk, Eels, etc.... What would be better:
Thin layer of sand, Deep layer of sand, CC?
I was thinking of using the black tahitian sand and some CC in my Wet/Dry for buffering. Pro's / Con's?
I am also thinking about taking out my Bio Balls and making that a Fuge. What is needed here? Just add LR back in place of Bio's? Is that it? Do I still use my filter pads at the top of my Wet/Dry?
How do you guys clean the sand if you don't syphon? With my fish list I doubt Lawnmower blennies and crabs will work as they would be quick meals. So how else do you keep the sand stirred and cleaned. Or do you only do water changes and don't touch the sand?
Help me get started right on this tank.
BTW, once I move my inhabitants out of my 75 into the 240 I will remove the CC from my 75 and go back with sand too.
That's for any help with these questions, as I want to set this thing up right from the beginning.

 

[superh]

my vote goes to a ~1 to 1.5" layer of sand...i'm pretty sure deep sand beds have their own problems

 

[stanlalee]

I knew there was a possibility that I wouldn't be able to keep a sufficient clean up crew so I went with a shallow sand bed (about a 1" layer). 1rst I set the powerheads flair nozzles up as best I could to gently blow the surface without creating a sand storm or bare bottom patches. this requires trial and error which you'll know is wrong when you wake up to a bare bottom, a mound of sand or a dirty area that obviously hasn't moved at all. you wont get it perfect but it helps. from there I simply manually go thru the sand with the back end of a long net. I've been doing this daily. Obviously you cant do this with a deep sand bed and I purposely went in knowing my sand is only there for decoration and not for filtration so disturbing it has not caused any issues. you can siphon out big stuff during water changes but you cant vacuum like you do crush coral. I have a few hermits but they are discrete due to a small valentini puffer.have one fire shrimp but except at night he stays in his den (he's bigger than the puffer and has not been bothered). have two astrea snails who only clean the liverock. Dont have any sand dwelling snails or anything else in the way of a clean up crew because I dont think my tank has been up long enough to sustain them ( if I have to feed them defeats the purpose) and even when I do not sure if the puffer will take a liking to them at some point so I planned it like I couldn't keep a clean up crew.
I have crushed coral in the tank I transfered my livestock from and other than vacuuming during water removal for water changes I never had an issue with it. nitrates and phospates always read zero but I used macro algae instead of a wet dry which job is to convert waste into nitrates. I'm gonna keep the CC in that tank.

 

[chilwil84]

if you have the room keep the wet/dry to make sure you dont get an amonia spike because large fish produce a lot of waste and add a fuge with some macro algae to help control you nitrates and save you sometime(not eliminating) on water changes

 

[v-lioness]

Have you considered a BareBottom tank in your FOWLR? My 300 is BB, I love it and would not go back to sand. When I do water changes I just syphon the bottom, plus I did not want scratches in my tank.
If you are just setting it up for a FOWLR now is the time to try it, you can always add sand later if you do not like it. If the tank is glass you must put something down (in-case a rock falls), in my 90g (glass) I have slate, because slate is non porous material or you can use the cutting board material (forgot the name of that stuff), my 300 is acrylic and I have nothing down.
Just a thought,
Kaye

 

[superh]

Originally Posted by V-Lioness
Have you considered a BareBottom tank in your FOWLR? My 300 is BB, I love it and would not go back to sand. When I do water changes I just syphon the bottom, plus I did not want scratches in my tank.
If you are just setting it up for a FOWLR now is the time to try it, you can always add sand later if you do not like it. If the tank is glass you must put something down (in-case a rock falls), in my 90g (glass) I have slate, because slate is non porous material or you can use the cutting board material (forgot the name of that stuff), my 300 is acrylic and I have nothing down.
Just a thought,
Kaye
Kaye,
Do you have any pics on the site for us to see what the tank looks like bare bottomed? I can understand the benefits with being able to syphon easily and all, but I think it would not be very aesthetically pleasing (no offense).

 

[v-lioness]

No Offense taken, our takes are all individual and I just go with what I like, I have been BB in this tank for 2 1/2 years or so. I am having a new stand built and adding 135g sump to this tank, I am adding a blue mirrored background toward the end of Feb.
Keep in mind if you do not like straight BB you can use slate or the cutting board material (you can have white, if that is the look you are going for).
My acrylic BareBottom, side view.

Rock area

Whole tank with open swimming

Kaye